The invention relates to an elongate electrical contact element for physically contacting an electrical component under test, comprising two electrical contacting end regions and an elongate intermediate region situated between the end regions.
Contact elements of this type are known in the form of spring contact probes or buckling beams. They are held by a contact element holder and serve to contact the electrical component under test with one end region and, with the other end region, to make contact with an electrical test apparatus, so that test current paths are created to the electrical component under test and the test apparatus can test the component under test for fault-free electrical function. The known contact elements configured as spring contact probes or buckling beams have circular cross-sections and produce contact forces when placed on contact surfaces of the component under test. In the case of a spring contact probe, its contact force is determined by a plunger which is impinged upon by a helical spring. In the case of a buckling beam, the contact force results from the intrinsic elasticity of the probe material. The buckling beam is deflected laterally into an arc shape by the contacting procedure and returns to the starting position following the contacting procedure. Due to components under test becoming ever more compact and the associated decreasing electrical contact separations, increasingly, problems arise with the aforementioned known contact elements. In other words, the small contact separations cannot be achieved with conventional technology, or they lead to contact elements unintentionally touching and creating short circuits. Furthermore, reductions in cross-section of spring contact probes or buckling beams that are necessary for space reasons lead to a reduced current carrying capacity together with reduced contact force. The smaller cross-sections can result in burning through if the test currents are required to be at a particular level. This burn-out mostly occurs at a distance from the guide apertures in which, for example, the buckling beams are guided. This is because the mechanical contact of the buckling beams with the walls of the guide apertures leads, in the immediate vicinity thereof, to conducting away of heat, which however is not the case further away from the guide region.